E21F 1/06
Duct connections
Official title: Duct connections (tube connections in general F16L)
E21F1/06 (Duct connections) appears on 7 US grants and 8 published applications in this corpus.
Search patents in E21F- Granted patents
- 7
- Published applications
- 8
- Assignees
- 9
- Inventors
- 13
- Latest grant
- 1 Sep 2020
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 2 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 1 |
| 2011 | 0 | 0 |
| 2012 | 1 | 1 |
| 2013 | 0 | 1 |
| 2014 | 0 | 0 |
| 2015 | 1 | 0 |
| 2016 | 0 | 3 |
| 2017 | 0 | 1 |
| 2018 | 0 | 1 |
| 2019 | 0 | 0 |
| 2020 | 2 | 0 |
By publication year. Applications have been published since 2001.
Recent patents
- Underground ventilation apparatus and method1 Sep 2020US 10,760,420 B2Polyvent PTY LTD
- Security for grate covering underground air vents14 Apr 2020US 10,619,884 B2Floodbreak, L.L.C.
- System and method for connecting two flexible containers6 Jan 2015US 8,925,973 B2Flecotec AG
- Ventilation duct assembly kit and method of assembly using the same25 Dec 2012US 8,336,925 B2Mecanincad Inc.
- Coupling for mine ventilation conduits9 Nov 1982US 4,358,139 APeabody ABC Corporation
- Security for grate covering underground air vents3 May 2018US 2018/0119982 A1Floodbreak, L.L.C.
- Underground ventilation apparatus and method21 Dec 2017US 2017/0362937 A1Polyvent PTY LTD
- Method, apparatus, and system for providing controlled atmosphere in confined spaces3 Mar 2016US 2016/0059047 A1Chembio Shelter, Inc.
- Method and apparatus for providing refuge passageways3 Mar 2016US 2016/0060951 A1Chembio Shelter, Inc.
- Method and apparatus for providing controlled atmosphere in mobile mine refuges3 Mar 2016US 2016/0061033 A1Chembio Shelter, Inc.
Most cited
By later US patents
- Ventilation duct assembly kit and method of assembly using the same4US 8,336,925 B2Mecanincad Inc. · 2012
- Flexible ducting joints3US 4,037,862 ACoal Industry (Patents) Limited · 1977
- Coupling for mine ventilation conduits3US 4,358,139 APeabody ABC Corporation · 1982
- Flexible ducting joint2US 4,014,569 ACoal Industry (Patents) Limited · 1977
- Underground ventilation apparatus and method1US 10,760,420 B2Polyvent PTY LTD · 2020